The present invention relates to a cassette for tape-shaped record carriers, and more particularly to a cassette for tape-shaped record carriers having optically viewable recordings. In particular, the invention relates to such a cassette which is to be inserted into an optical readout device so that the device is capable of reading the recordings provided on the record carrier in the cassette.
There are many applications where tape-shaped record carriers are used which are provided with optically viewable recordings, for example recordings which are produced on them by stilii or the like. These recordings are then subsequently read in an optical reader, and it is customary in many instances to mount the record carrier on hubs which are secured in an open frame. In many instances, this frame can be made exchangable or it can be so constructed that it can be removed from the reading device or registering device, as the case may be, for maintenance and inspection and for changing the tape hubs which are mounted in the frame so that new tape hubs with a new tape-shaped record carrier can be mounted in the frame.
However, in many instances these prior-art arrangements are not satisfactory. Particularly where the recorded carrier is to be subjected to subsequent operations, for example for the purpose of analysis of records provided on it, such as the analysis of times, quantities or the like that are recorded on the record carrier, the prior-art arrangements provide insufficient protection against mechanical damage to the record carrier. Evidently, if mechanical damage occurs, the record carrier may become mutilated and the record may then be wholly or partly destroyed. Also, many of the prior-art arrangements are not even completely removable from the reading device, but can only be flipped to an outwardly accessible position for the change of the tape hubs. Particularly disadvantageous in the prior-art arrangements is the fact that they are not suitable for employment in a machine analysis of recorded data on the record carrier, because they cannot be properly stored without the danger of damage to the record carrier and for the same reasons they cannot be readily transported.
It is already known to provide tape cassettes having magnetic tape therein, such as the so called "Phillips" cassette. However, these cassettes are not suitable for use with tape-shaped record carriers which are provided with optically viewable recordings, because they do not permit a viewing of the recordings of a record carrier within the cassette housing. This is not necessary in the cassettes having magnetic tape. Moreover, in that type of cassette, no problems exist in terms of providing an optimum positioning of the tape with respect to the position of the recording device and/or reading device.